A. Field of the Invention
The present invention relates generally to video surveillance systems, and more particularly, to the use of a mobile wireless network for transmitting a real-time video signal from a camera at a remote location, to a Central Monitoring Office (CMO). U.S. Pat. No. 5,850,592 entitled xe2x80x9cMethod for Self-Organizing Mobile Wireless Station Networkxe2x80x9d discloses the specific details of the mobile wireless network used in this invention and is incorporated herein by reference.
B. Description of the Related Art
One type of conventional video surveillance system consists of cameras that are deployed at remote locations that are desired to be monitored by security personnel. The images from the different cameras are displayed on one or more video monitors at a security console. This type of surveillance system has been effective for improving security in a monitored facility because the system provides images to the console in real-time, and the operator of the system can take immediate remedial action. In order to maintain the system operating at a relatively low cost, the remote locations have to be fixed (i.e., non-mobile remote locations).
The problem of violence between students while on school buses (70,000 school buses in North America) is an escalating one. Numerous reports on television show fights that take place in school buses. Because of this problem, many school districts in North America use video surveillance on school buses. Problems of violence and other illegal activities are common on other forms of public transportation as well.
In another type of conventional video surveillance system used in school buses, video cameras and recorders are placed in a remote and mobile location. School municipalities use this system to monitor violence on buses and prosecute offenders. The operator of the surveillance system (i.e., the school officials) places a video camera recorder in a sturdy tamper-proof box in the interior of the school bus, so that the camera can record images of the interior of the bus. If a violent event takes place on the bus, the bus driver would notify school officials, who remove the videotape from the recorder. The school official uses the videotape to identify the perpetrator of the violence and take disciplinary action. In this type of system, however, real-time information is not provided to the operator of the system. Instead, the images are recorded and then reviewed by the operator. The operator only learns about the violent events long after the event took place, when the damage has already been done. In addition to this disadvantage, without real-time information available there is no knowledge of the geographical location of the vehicle. Thus, the advantage of this second conventional system over the first conventional system is that it facilitates video surveillance from remote, mobile locations. The disadvantage of using this system consists in that the video image provided is not a real-time image, and therefore, the operator of the system cannot take immediate remedial action.
There are techniques that could be used for transmitting video or data signals from a mobile vehicle to a central location, but they all have intrinsic costs or problems. One such technique is direct broadcast. In direct broadcast a video camera is attached to a radio transmitter that directly transmits the image captured by the camera to a CMO. The transmission scheme of this technique has a limited range and runs into problems related to the transmission of a radio signal through obstacles such as tall buildings. Radio transmitters that can go longer distances are physically large and expensive.
An alternative to the use of direct broadcast radio transmitters is to use a third party communication service, such as a cellular telephone company. The cellular network would be used to transmit data from a camera at a remote mobile location to a CMO. Specifically, the Cellular Digital Packet Data (CDPD) standard for data communications (as opposed to simply voice communications) in a cellular system could be used. The main disadvantage of using a third party communication service is that the vehicle would need to establish and maintain an expensive link to a central cell tower (the user is charged on a per-minute basis) for using the CDPD cellular telephone service. This method tends to be expensive and requires the presence of cell towers in the vicinity of the operator""s transportation service.
Therefore, there is a need for a video surveillance system that facilitates the transmission of real-time information, including sound, image, and geographical location data, to a CMO from a remote and mobile location, wherein such information transfer is cost effective.
Accordingly, it is an object of the present invention to meet the foregoing needs by providing systems and methods that perform real-time video monitoring of a remote and mobile environment in a cost-efficient manner.
Specifically, a system for meeting the foregoing needs is disclosed. The system includes at least one input monitoring unit that monitors an environment and produces a video and an audio signal corresponding to the environment; a CMO that displays image and sound information corresponding to the video and audio signals; and a self-organized mobile wireless communications network. The at least one input monitoring unit is remote from the CMO and transmits the video and audio signals to the CMO over the wireless communication network.
Both the foregoing general description and the following detailed description provide examples and explanations only. They do not restrict the claimed invention.